This invention relates to a fluid dispensing nozzle, and in particular to the type of nozzle conventionally used in the dispensing of gasoline. A typical such nozzle is described in U.S. Pat. No. 3,540,496 to Myers and in my U.S. Pat. No. 3,757,834, the disclosure of which is hereby incorporated.
As set out in U.S. Pat. No. 3,757,834, gasoline dispensing nozzles conventionally include a casing having a main valve, a manually operable lever, and an automatic high-level shut-off means which forms a pivot for the lever. The shut-off means includes a plunger which is slidably mounted in the casing. The forward end of the lever is pivotally secured to the lower end of the plunger. When gasoline reaches the end of the dispensing nozzle, the plunger is allowed to drop to a point at which the lever is no longer able to open the main valve of the nozzle.
In the present commercial practice, the plunger is molded of plastic, such as a homopolymer acetal resin sold by E. I. DuPont de Nemours & Company, Inc. under the trade name Delrin. The lower end of the plunger includes a transverse hole. The lever is commercially formed from sheet metal to have a U-shaped cross-section with a pair of upstanding side walls and a lower web part. At the forward end of the lever the web portion is cut away, and holes are provides in the up-turned sides. A pivot pin passes through the holes in the plunger and the lever and is trapped between the up-turned sides of a hand guard which surrounds the end of the plunger and the lever.
It has been found that the lower end of the Delrin plunger frequently breaks off in use. Although this breakage does not create an immediate danger, it does render the nozzle unusable until the entire nozzle is rebuilt and therefore constitutes a serious annoyance and a considerable expense to the user.